Your phone will last far longer if it goes into “deep sleep” whenever possible. If you have a lot of apps, some of them may be keeping your phone ‘awake’, just to communicate with home base. An Android app called Better Battery Stats will run down exactly what is waking up your phone, and enable you to turn it off. If you can keep your phone in ‘deep sleep’, it’ll last.

Switch screensaver

Don’t use animated screensavers. It even makes a difference to switch to a black, or dark, screen background so it doesn’t burn as much electricity when you’re in the menus.Shut down apps you don’t need

Make sure your phone isn’t running apps in the background. On iPhone, you can check by double-tapping the Home button, then pressing ‘X’ to shut ones you don’t need. If you’re unsure, restart your phone to banish apps that might be running without you knowing.

Use an app to last longer

Green Power for Android is superb. It shuts down your data connection if the screen is off, then you set it to check for emails, say, every ten minutes. On its own this app can double your battery life. It’s recommended by several networks in U.S. and is now available in the UK.

Ditch Bluetooth, GPS and Wi-Fi unless you're using htem

Switch off wi-fi, Bluetooth, and GPS unless you need them. This will immediately add about a third to your battery life. Lots of people leave them on all the time. On both iPhone and Android, controls to do this are easily accessed via phone menu.

Turn off voice control

Apple and Samsung, both fill your phone with their own apps - disable these wherever possible, especially voice control apps that use the phone's microphone. Never use Apple’s Siri voice control, it’s murder on your battery, likewise Samsung’s S Voice. Make sure your phone isn’t running other Apple/Samsung apps you don’t need or want.

Check your battery

If your phone gets hot while you use it, it could be that your battery is on its last legs. New ones are cheap on eBay, and if your phone’s old, you can also get ones with much higher storage than the ones it shipped with. Sorry, iPhone owners, this won’t work for you - you can’t take the back off.

Don’t charge it to full

Eric Limer of Gizmodo says that “battery memory” means that you should never run your battery empty - and avoid charging it to full. “You should try to go from around 40 percent to around 80 percent in one go, and then back down whenever possible,” says Limer. “A bunch of tiny charges isn't as bad as going from 100 down to zero all the time, but it's not optimal either.”

Switch off 3G and 4G

If you’re running low, switch off 3G. This can double the battery life of a dying phone - basically, there are at least two aerials working all the time in most phones, so if you switch to 2G, it’ll still work as a phone and for texts, but will last twice as long, just like phones did in ‘the good old days’.

Accessorise

If you’ve followed the above tips and your phone battery still doesn’t last very long, it’s time to consider a charging accessory. The Mophie JuicePack Air (£40) fits over your smartphone, doubling the battery life, alternatively if you don’t fancy changing the look of your phone consider a portable battery charger like Proporta TurboCharger 7000 (£54).